Now, when coming to how these magnets
work, it gets a bit tricky due to the scientific jargon, but please bear with
us. Typical permanent magnets are made of ferromagnetic materials which
generally include the elements like Iron, Nickel and Cobalt, their alloys and
some rare-earth metal compounds. A property of these ferromagnetic materials is
that they possess a very weak, but naturally occurring magnetic field that is
created by the electrons that surround the nuclei of their atoms. Now these
atoms are present in groups called domains which, within themselves, act like
permanent magnets with a North and South pole of their own. In a magnet, there
are multiple such domains but their orientations cancel each other’s magnetism
out i.e. their corresponding North and South poles interact to negate each
other’s magnetic field.

Keeping this in mind, a simple
inference we can make is that these ferromagnetic entities will get magnetised
if their domains stop cancelling each other out and instead point towards a
single direction leading to the generation of a single magnetic field. Similar
to how a blacksmith heats a piece of metal before moulding it, this process of
aligning all the domains and bringing a material to its magnetic saturation
point is achieved by heating a ferromagnetic material at incredibly high
temperatures and exposing them to a very strong external magnetic field at the
same time. Upon doing so, all the domains would line up as per the
external field and when the material is then cooled down, the domains get locked
into their aligned positions. After the external magnetic field is removed, the
domains will remain aligned thereby creating a very strong permanent magnet.

A: Quite
similar to identifying the poles of the Earth, the best way is to use a
compass. The only difference being, the end of the needle that normally points
towards the North Pole of the Earth would actually be the South Pole of
the magnet.

Another simple way is to use an
existing magnet with its poles marked. In which case, the North Pole of the
marked magnet will point to the South Pole of your unmarked magnet.

Neither of the two poles is
stronger than the other. They are both equally as strong in order to create a
uniform magnetic field i.e. a field with uniform magnetic field strength
distribution.

·Permanent
magnets : Emit magnetic fields without the
need for any external source of power. Once magnetized, they hold on to their
magnetic properties.

·Temporary
magnets : Behave as magnets while attached
to or close to something that emits a magnetic field, but lose this
characteristic when the source of the magnetic field is removed.

·Electro-magnets :
Require electricity in order to behave as a magnet. The magnetic field
disappears when the electric current is turned off. Typically, electromagnets
are used in conjunction with a solenoid and a ferromagnetic material (which we call the iron core) placed in
it gets magnetised or demagnetised with the electric current.

A: Here’s
some good news - magnets can retain their magnetism essentially forever if used
and stored appropriately, i.e. away from factors that adversely affect magnetism.
Some of these factors include:

·Heat

·Radiation

·Close
proximity to very strong electric currents

·Close
proximity to other magnetics of like polarity

·High humidity
may corrode neo magnets (unless if they have protective coating)

However, modern magnet materials do lose a very small fraction
of their magnetism over time. For example, Samarium Cobalt materials may lose
less than 1% of their magnetism over ten years. Not too bad, is it?

A: Absolutely. Magnets can be re-magnetized to their original
strength, unless if your magnet has been damaged by extreme heat – that’s
something you might want to avoid! However, iindustrial grade super powerful magnets cannot be re-magnetised easily in your home or lab, requiring a high current magnetiser.

A: You will come across many different terms when it comes to
measuring magnet strength and this just calls for more technicalities here.
Three of the most commonly used terms are Pull, Gauss and Hysteresis:

Pull refers to how much force is needed to pull the
magnet off of a steel surface. It is measured in kg, using a Pull-tester.

Gauss is a measure of magnetic induction. Simply put,
a magnet’s Gauss measurement represents the number of magnetic field lines per
square centimetre, emitted by a magnet. The higher the value, the more lines of
magnetism emitted by a magnet. Gauss is measured using a Gaussmeter or flux
meter, and gives a reading of the number of lines of magnetism in every cm2 (1 Gauss = 1 line of magnetism in
1 cm2), also known as flux density.

However, note that Gauss alone doesn’t give a full
picture of a magnet’s strength. Apart from the material, the geometry of the
magnet also has an effect on its Gauss value. For the same surface Gauss value,
a larger magnet will be much stronger than a smaller one. What this means is
sometimes a small magnet may have a higher surface Gauss but will be able to
support less weight than a larger magnet with a lower surface Gauss.

Lastly, hysteresis simply refers to a delayed response
to an applied stimulus. This stimulus could a magnetic field with a delayed
magnetization or flux density. A hysteresis graph can be created by repeated
magnetisation and demagnetisation within a closed circuit situation and
plotting a corresponding induced magnetic flux density vs magnetising force
graph (BH). The stronger permanent magnets would be made of materials that have
a larger area within this hysteresis loop graph.

A: Yes. The basic idea is that the strength of a magnetic
field reduces almost exponentially with increasing distance.

If you want to get a little bit deeper into the
physics, an estimate of magnetic field strength can be made for a circular
magnet with a radius, R and Length, L, the field at the centerline of the
magnet a distance X from the surface using the following formula (where Br is
the Residual Induction of the material):

A: There’s strength in numbers! Using two identical magnets together
would be the same as having one large magnet of their combined size,
essentially doubling the magnet’s strength and pull. However, an optimum level
of working is obtained once the length of the magnet exceeds the diameter of
the magnet. Any further additions to magnetic length will provide only small,
rather negligible, increases in performance.

A: The
specified pull force may not be achieved for all magnets in real
world conditions simply because the specifications are obtained by
testing in labs under controlled conditions. There are multiple factors that
could lead to a reduction in the effective pull force. Some of these factors
include:

A: Flux Density of the magnetic material is
directly related to the Pull Force per square 'cm' (or 'mm') of
the magnets that are used. The Pull Force number takes
into account the size and shape of the magnet along with the flux rating of the
material from which it is made.

A:The highest temperature at which a magnet can be
effectively used, largely depends on the 'permeance coefficient’ – a function
of the circuit the magnet is operating in. The higher the permeance coefficient
(the more 'closed' the circuit), the higher the temperature at which the magnet
can be operated without becoming severely demagnetized. Shown here are
approximate maximum operating temperatures for the various classes of magnet
material. Its best to avoid reaching these temperatures for these specific
materials

A: To efficiently order magnets, you need
to have a good idea of what you want to accomplish. Here are a few things to
keep in mind:

1.What is the nature of the intended
application (e.g. holding, moving, lifting, etc.)?

2.What is the desired shape of the magnet
(e.g. disc, ring, rectangle, etc.)?

3.What is the desired size (diameter,
length, width, height, etc.)

4.Tolerances - what variation in
dimensions is allowed?

5.What conditions will the magnet be used
in (e.g. elevated temperatures, humidity, outside, inside, etc.)?

6.What is the required strength of the
magnet (e.g. in terms of Gauss, pounds of holding force, etc.)?

7.Cost - what is your budget? This will
eliminate certain materials from consideration.

8.Quantity - how much do you need?

16.Is it
possible to cut or drill through magnets?

A:Yes, but only
certain magnets. Generally magnets are extremely brittle and it is best to derive the required size at the outset rather than to try and machine a larger magnet down to size. Flexible magnets can be cut down to size or drilled through.
Neodymium magnets are the strongest magnets in the world - they can be
machined, but we recommend only experienced machinists perform this task (we
elaborate on this further in the FAQ section on Neodymium magnets below. Check
it out if you’re interested!)

17.Is it
possible to block a magnetic field?

A: A magnetic field cannot be blocked, they can only be redirected.
For redirecting, the elements must be able to interact with the field i.e. get
magnetized, hence the only elements that make the cut are the ferromagnetic
materials. This includes the Iron, Nickel and
Cobalt and their associated compounds. However, it may be noted that the degree
of redirection is directly proportional to the magnetic permeability of the
material. The most
efficient shielding material is the 80 Nickel family, followed by the 50 Nickel
family. An example of such a high permeability nickel-iron alloy is 'mumetal' which is quite effectively used to redirect the magnetic field.

18.What
precautions should I take while working with magnets?

A: Though magnets seem to be quite
fun things to have around, care should be taken when handling and storing them.
Here are some tips for the same:

1.Always be careful! Magnets can snap
together and injure personnel or damage themselves.

2.Just to play it safe, keep magnets away
from magnetic media - such as credit cards and computer monitors.

3.Store magnets in closed containers, so
that they don't attract metal debris.

4.If several magnets are being stored,
they should be stored in attracting positions.

5.Alnico magnets should be stored with
"keepers" (iron or magnetic steel plates that connect the poles of
the magnet) since they can easily become demagnetized.

6.Magnets should be kept away from
pacemakers!

19.What
techniques can I use to assemble magnets with my devices?

A:You may use mechanical means, or simple adhesive
means. Most commonly though, adhesives are used for securing magnets. Special
care must be taken for the type of adhesives being used as for instance, uneven
surfaces call for adhesives with more ‘body’ to conform to the irregularities.

Specifically,
hot glues have been found to work well for adhering magnets to ceramics, wood,
cloth, and other materials. For magnets being adhered to metal, 'super-glues'
can be used very effectively.

We can
supply Flexible magnets with an adhesive already attached to the magnet: all
you need to do is to peel off the liner and attach to your product.

Do note
that for all of the above to be applicable, it is pretty important to ensure
all surfaces being bonded are clean and dry before bonding.

20.What
adhesives can I use for attaching magnets to my devices?

A: Yes, using a two-part epoxy adhesive has been known to work best
for this scenario. We recommend Araldite Rapid or Loctite Industrial
strength Adhesive both of which have a similar track record on reliability and
speed with a setting time of about 5 minutes.

21.Which
type of magnets can I use to make fridge magnets?

A: Most fridge magnets are made of either flexible rubber or
ferrite magnets on the back. This is referring to the general ones you purchase
off the regular souvenir stores. While they are not as strong as neodymium magnets, they
provide great value for money and can conveniently hold the lightweight items
you would normally expect fridge magnets to withstand. In addition, if we may
so ourselves, they make for a wonderful decorations that would add to the
excitement one generally has when approaching the fridge.

OUR ONLINE STORE

ORDERS

22.Do you
have a minimum order policy?

A: While
we do not have a Minimum order quantity, we do specify a minimum order value to
checkout from our store and that is US$15. Every shipment of magnets require special packing and for a quantity of 2 or 2000, the care taken is quite similar. It does not make sense for us to expend that effort unless there is a minimum value for the service.

23.Can I
return or cancel my order?

A: It’s
alright if you change your mind. Supreme Magnets accepts returns on all magnets
in original and resalable condition within 30 days of purchase, subject to
terms and conditions.Please see our Return Policy for details regarding returns and refunds.

LOCATION

24.Where
is your office located?

A:Our main office facility and
warehouse are located in a quiet industrial neighborhood in a nifty western part of Singapore, quite easily accessible from everywhere. If you live nearby, feel free to walk-in or
pick-up your purchase from our office. Otherwise, you can browse through our
website catalogue and directly order from our plethora of online collection. Our address is at 196 Pandan Loop, #02-11 Pantech Biz Hub, Singapore 128384.

25.Do you have any local distributors or retail stores?

A: No, we don’t have any local distributors for our raw magnets. We do however encounter many cases of resellers buying off our store and selling to their customers, because we are one of the cheapest while being the best, However, you can purchase our products online through our website, by email,
phone, or fax. We’re just a click away!

PAYMENT

26.Do you
offer Cash on Delivery?

A:This option is available
only for customers in Singapore, who choose to self-collect their orders.
Currently, we are unable to arrange Cash or Cheque collection for deliveries by
Registered Post or local courier. Please see our Payment & Returns Policy for more details.

SHIPPING

27.When
will I receive my order?

A: This
depends on the shipping method and which part of the world you are at. Local delivery would take around 1-2 days,
while Sing Post Surface Parcel (by Sea) might take up to 4 weeks. DHL/Fedex for overseas shipments can take upto 4-5 days max.

28.Can you
deliver to my location?

A: We can deliver in any part of the world accessible to snail mail and the friendly Courier man! Please
visit our website’s Shipping Information and select a delivery option suitable for your
location. Our preferred shipping carrier is Singapore Post by registered air mail,
air parcel or local mail. However, during checkout we offer you the option of
Singapore Post or express courier (slightly more expensive) for you to choose. The indicative price is
displayed alongside your option so you may choose accordingly.

29.Are
there any regulations for shipping magnets?

A: There are very specific guidelines for the shipping of magnets
by air while no such restrictions exist on shipping your magnets by ground.
According to SingPost’s General Prohibitions and Dangerous Goods Guide, a magnetized material is considered
dangerous for air transport if it has a magnetic field strength of 0.159 A/m
(0.002 gauss) or more at a distance of 2.1 m (7 ft) from any point on the
surface of the assembled package. Thus, if you are unsure of your magnets’
field strength, ship by ground.

30.Can you
just put my magnets in a small envelope to save postage?

A: While we do understand your concern, our shipping
policies have to comply with the safety guidelines of various governments and
the different freight carriers, especially is they are being shipped by air.

OUR PRODUCTS

CUSTOM MAGNETS

31.Do you
offer customizable shapes for neodymium magnets?

A: Absolutely! Feel free to contact us with any special
requests.

32.Do you sell monopole magnets?

A: We’d love to, just that they don’t
exist yet. All magnets need to consist of two poles to create a surrounding
magnetic field and we haven’t been able to isolate these individual poles
yet.

33.Do you
provide magnets with one pole on an inside surface and one pole on the outside?

A: This is still a work in progress with the
ring shaped magnets. They are generally referred to as being “radially
magnetised”. However, this feat is simply not possible with disc, cylinder, and sphere shaped
magnets.

34.Why do the pull force values differ between Supreme’s
calculator and another online calculators?

A: This
is because we don’t rely on the inaccurate formulae even though they would’ve
made the job a lot simpler. Instead our engineers have worked out a unique
calculation method, far more accurate than any formulae as it utilises several
test cases and has been derived after long hours in the laboratory. The basic
test involved the plates being pulled apart until the magnet disconnects from
one of the plates. The peak value of the applied force is recorded as the
"pull force". Do note though, if using steel that is thinner, coated,
or has an uneven or rusty surface, the effective pull force may be different
than recorded in our lab.

A: You ask for it and you shall have it. We
do supply the BH curves for all our magnets upon our customers’ request

NEOMAGNETS

36.What
are neo magnets, and how are they made?

A:Neodymium is a member of
the "rare earth" elements on the periodic table. Its magnets are
actually the strongest of the rare earth magnets and are the strongest
permanent magnets in the world!

Neodymium magnets are composed of –
you guessed it – neodymium, but also contain iron and boron. They are made by
compressing a powdered mixture of the three elements under great pressure into
moulds. This material is then sintered (heated under a vacuum), cooled, and
ground or sliced into the desired shape. Coatings may also be applied if
required. Finally, the blank magnets are magnetized by exposing them to a very
powerful magnetic field in excess of 30 KOe.

37.What
are the various applications of these magnets?

A: Just about anything under the sun! Some of the common
usages1 seen today are:

2.Commonly used in magnetic separators,
filters, ionizers, in production of on–off buttons, safety sector and security
systems.

3.Grease filter producers use neodymium
magnets in metal separators to more effectively filter out iron powder in oil.

4.Additionally, they are beneficial in
covering machines, cars with awning and in the production of magnetic tool
belts.

5.They are also used in jewellery clips,
identification badges and in the production of baby strollers that are attached
to carriers via magnets.

6.The health sector is another field where
neodymium magnets are incorporated in medical devices for example in magnetic
resonance imaging devices to diagnose and treat chronic pain syndrome,
arthritis.

2.To prevent them from attracting any nearby debris, they must be
kept in closed and clean containers.

3.Ensure they are not stored near any electronic equipment or
magnetic storage devices.

40.Do they
get weaker with time?

A: Barely. Neodymium magnets are the strongest and most
permanent magnets known to man. They lose less than 1% of their magnetic
strength over 10 years as long as they are not damaged by extreme heat or
physical wear and tear. That’s barely enough for you to notice unless if you
have very sensitive measuring equipment!

41.Is it
possible to machine neomagnets?

A: The material that these magnets are made of – Neodymium, Iron and Boron
– are very hard and brittle. Machining it would be difficult at best. The
hardness of the material is a whopping RC46 on the Rockwell "C"
scale, which is harder than most drills and tooling, so these tools would
likely heat up and become damaged if used on the magnets.

42.How do we then shape this stuff?

A: Diamond tooling, EDM
(Electrostatic Discharge Machines), and abrasives are the preferred methods. We
suggest that the machining of neodymium magnets should only be done by
experienced machinists who are familiar with the risks involved: for starters,
the heat generated during machining can demagnetize the magnet and cause it to
catch fire. Machining also produces dry powder which is very flammable, so
great care must be taken to avoid combustion of this material.

43.Once
fully magnetized, can the magnets be made stronger?

A:Once a magnet is fully
magnetized, it is saturated and cannot be made any stronger. If it helps, you
can stack magnets together – this would be the same as using a larger and
stronger magnet.

44.Are
neodymium magnets affected by temperature?

A: Until a certain range they are good to go. But once we hit their
Maximum Operating Point (80°C) we start losing a fraction of
the magnets strength, and this is especially the case for Standard N grades.
Now, if these magnets are heated beyond their Curie temperature, they will lose
ALL there magnetic properties. These operating and Curie temperatures are
material properties and they differ even between the various graded of
Neodymium itself.

45.Can
these magnets withstand soldering or welding?

A: Please don’t try that! The heat would demagnetize the
magnet, which could cause it to catch fire and pose a safety risk.

46.How do
you rate your neomagnets?

A: We normally measure
our surface field density, aka the magnetic field density, at the surface of a
magnet using a Gaussmeter. This value is tested and specified for each of our
stock magnets. This is the most practical measurement as compared to other
readings such as the Residual Flux Density (BrMax) (which actually estimates
the strength inside a magnet where we probably will never find ourselves at).

47.Are
your neomagnets RoHS compliant?

A:Yes, our magnets are
fully RoHS compliant, meeting the European Parliament Directive entitled
"Restrictions on the use Of Hazardous Substances" (RoHS). This
Directive prohibits the use of the following elements in electrical/electronic
equipment sold after 7/1/2006: cadmium (Cd), lead (Pb), mercury (Hg),
hexavalent chromium (Cr(VI)), polybrominated biphenyls (PBBs) and
polybrominated diphenyl ethers (PBDEs).

48.How is
maximum operating temperature different from the Curie temperature of magnets?

A:The maximum operating
temperature is the maximum temperature the magnet may be continuously subjected
to, with no significant loss of magnetic strength. The Curie Temperature is the
temperature at which the magnet will become completely demagnetized. At
temperatures between these two points, a magnet will permanently lose a portion
of its magnetic strength. The loss will be greater the closer to the Curie
Temperature it is heated.

49.What
does the N value of your magnets represent?

A: The
maximum strength up to which a magnet can be magnetized is represented by its
grade or N Value. This value actually refers to the Maximum Energy Product
expressed in the units of millions of Gauss Oersted (MGOe). Generally speaking, the
higher the grade, the stronger the magnet.

50.What
field strength is required to magnetize a neomagnet?

A:As a general rule of
thumb, a peak field of between 2 and 2.5 times the intrinsic coercivity is
required to fully saturate a magnet. For standard neodymium magnets, the field
required is minimum of 24 KOe, with 30KOe being the standard.

COATINGS

51.How do we choose between the
different plating and coatings?

A: Coatings are chosen based on the user’s
preference or on the intended application of the magnet. They don’t affect the
magnet’s strength, but can often protect it, for e.g. from corrosion. The most common material used for plating neodymium
magnets is Nickel, which is used in conjunction with copper as a triple
nickel-copper-nickel plating. Not only does it give a polished silver finish,
but it also provides good protection from corrosion. You may have also seen
black nickel used as a coating – this has a shiny black appearance and is a bit
more resistant to corrosion than regular nickel.

Another common plating material is
Zinc. Zinc provides a dull grey/bluish finish, and is more susceptible to
corrosion than Nickel. It can sometimes leave behind a black residue on the
items it comes in contact with.

Epoxy, another coating material, is a
plastic coating which is fully resistant to corrosion, but is the least durable
of the common coatings.

Gold plating can also be used – it
has similar characteristics as nickel plating, but is much fancier with its
gold finish!

52.Why do we plate or coat most
neodymium magnets?

A: The material Neo magnets are made of contains Iron,
which oxidises easily if exposed to moisture. You must have observed how even
normal humidity can rust your Iron tools and wires. Plating or coating the magnets
protects the Iron from rusting or corroding, extending life of the magnet.

53.Would painting over the nickel
plating affect its performance?

A: All paints that are
formulated for use on metal surfaces can be used on nickel plating. We find
that spray-on paint works best.

54.Do plastic- and rubber-coatings weaken the magnet?

A: These materials don't
"weaken" the magnet. It is just that a layer of plastic or rubber
creates a large distance between the magnet and metal surface which reduces the
pull force.

55.How thick is your magnets’ nickel
plating?

A: With a total thickness of about 17-20 µm, the nickel plating is actually a triple
plating of Nickel(Ni)-Copper(Cu)-Nickel(Ni). Each layer has a rough thickness
of about 5-6 µm for the Nickel layers and 7-8 µm for the Copper layer.

56.Can you provide unplated magnets?

A: Due to the constant fear of oxidisation of the
iron in the NdFeB material, unplated magnets are not stocked. However, these
can be supplied as custom order items. Just feel free to write in to us if you
want to place your order.

MAGNET SAFETY AND HANDLING

HEALTH AND SAFETY CONCERNS

57.What
are the safety concerns associated with neo magnets?

A:There are no known health
concerns with exposure to permanent magnetic fields. However, precautions must
be taken when using these magnets around children. Magnets can be very
dangerous if swallowed or if they trap a child’s fingers. We aren’t medical
professionals, hence our best piece of advice will be to please consult your
physician for any medical risks you may face with regards to magnets.

58.Are
magnets dangerous for people with pacemakers?

A: Magnets
can cause pacemakers to operate in a mode that does not respond to the user’s
own cardiac rhythm, and should therefore not be placed in close proximity to
the pacemaker. Please consult your doctor for further information.

59.Can
magnets damage my electronics?

A: Strong
magnets such as neodymium magnets can damage certain magnetic media, such as
credit cards, video tapes, magnetic ID cards, etc. They can also damage
televisions, computer monitors and other CRT displays, and should therefore not
be placed near these appliances.

The same isn’t true with hard drives
or your smartphone memories as every
hard drive already contains powerful neo magnets while phones contain small
magnets within them, so one moving around outside the case will not affect
their stored data.

Similarly, small magnets do not
damage electronics. Magnets also do not harm appliances such as refrigerators,
stoves, ovens and microwaves.

60.Does my product require a specific safety warning if
it contains a magnet in it?

A: It
really depends on the application of your product, the size of the magnet(s),
how the magnet is used, and where the magnet is located within the product. We
recommend providing any warnings that you think may be an issue.

OTHERS

61.If two
strong magnets are attached to each other, how can I separate them?

A:You can simply use your
hand force to separate the small to medium sized magnets by sliding them off
their surfaces. For the medium to large magnets, the previous technique won’t
be feasible. So we will take the assistance of the corner of a table and use
our brute force to push the magnets off each other. For very large magnets
(generally 2" and larger) neither of the techniques can be used, instead
we use a specially made magnet separating tool. Write to us for details and we shall be happy to furnish more information.

62.How can
I clear away metal dust from my magnets?

A: Adhesive tape should do the trick! It is the best way to
clean magnets.

63.How can I make my magnets impact
resistant?

A: An easy way to protect your
magnets is to wrap them with a few layers of electrical tape. This would
protect them from most damage from collisions with hard surfaces. Another
way to protect your magnets from damage due to impact or due to other elements,
is to give them a rubberized coating. We find that this works great to protect
magnets from wear and tear.